Our major emphasis in this project continues in the areas of DNA uptake, the specificity of Haemophilus binding, the requirements for binding of plasmid and chromosomal DNA's and developing systems for studying the recombination of donor and recipient DNA during transformation. A number of important developments have occurred during this past year, including 1) the use of recombinant DNA to dem nstrate the process of specific DNA binding by Haemophilus, 2) the discovery of two systems for studying the apparatus used by the cell to bind DNA in a DNase resistant form and 3) the development of recombinant molecules that carry segments of Haemophilus DNA that permit one to analyze the mechanism of recombination of donor with recipient DNA.